This phenomenon can be stumbled upon around 300 m from the lower station of the Świeradów-Zdrój Ski&Sun Gondola Lift (in the direction of Czerniawa-Zdrój). A car with its engine off here appears to roll uphill.
Some claim that the inclination of the road surface is simply an optical illusion, while others contend that this is a gravitational anomaly. All involved have plenty of fun.